I Corinthians 9  - Paul uses his own life as a testimony of what it means to put love first.. before knowledge, before personal needs, and even before his "rights" as an apostle of Jesus Christ.

As a called and proven apostle, Paul had the right to freely eat or drink;  to have a wife along side him; to receive pay for his work and earn his living "from the gospel."   Even according to the Law of Moses "You shall not muzzle the ox while he is threshing."  All those who were priests and Levites earned their living through the work in the temple.  Paul, a willing and diligent minister of the gospel, should have received support from the churches that he served... but he didn't .

Instead of demanding that he be paid, Paul determined to "offer the gospel without charge" .  He chose to act like a "slave to all", for the sake of the gospel.  He wanted more than anything.. more than pay, more than food, more than respect or power.. for people to be saved. 
 So, he:
chose to be weak to the weak;
chose to be under the Law to those who were under the Law;
chose to be without the Law to those who were without the Law;
"And I do all things for the sake of the gospel, that I may become a fellow partaker of it." (v23) 

Paul was fully committed to the ministry of the gospel of Christ.
He ran the race is such a way that he would win.
He was like an Olympic boxer.. aiming to win, not just "beating the air".
He disciplined himself, his own body,  for the sake of the Word of God.

How much do we sacrifice for the gospel?  What have I done that others might hear the Word and come to the salvation through Jesus Christ? Have I become a "slave" to any.. that they might find Jesus?  I am also a "steward" of the gospel.  I can offer it freely to those who need hope and love and faith.. do I?

Father in heaven,  forgive me for withholding the Word of life to those who are dying.. Open my eyes to see those who are weak, those who are enslaved to the law, and to those who are enslaved by sin.  Give me the words to speak up and to testify of the salvation found in Christ Jesus the Lord.  I pray this in His name. amen.